Dan Carter must undergo surgery to remove bone spurs in his right ankle, an operation described as "similar to what he had done a few years ago".

All Blacks doctor Tony Page, meanwhile, said Carter did not need surgery to repair the Achilles injury that marred his 100th Test, against England and Twickenham, and forced him subsequently to miss the victory against Ireland in Dublin that completed the All Blacks' perfect season.

"Dan's Achilles tendon has developed some wear and tear but it won't require surgery, which is good news," Page said in a Fairfax NZ News report.

Carter has plenty of time to recover from the surgery as he is now on a six-month sabbatical granted by the New Zealand Rugby Union to prolong his career. He is not required to return to the Crusaders until early July.

"Once he has recovered from the bone spur operation, he will have a period of rest followed by gradual loading of the Achilles and calf to allow it to recover and repair ahead of his return to rugby," Page said.